What thermostat is in a 500efi... 140 or 160?
 

I'm just curious if anyone knows what themostat is in a 500efi. I need to replace mine and a MERC dealer is telling me its supposed to have a 140 thermostat but I'm pretty sure the one I removed is a 160 themostat. Thanks

Here, look at parts per your engine serial #: http://www.mercruiserparts.com/500-efi

The few ranges I looked up where 140*F, but there are way more than a few serial # ranges.

Is yours heat exchanged or raw water cooled? Mine has 160 but I'm raw water cooled.

I think you'll find the heat exchanged once are 140.